Machine screws are used in mechanical structures to hold parts together. In order to provide some resistance to vibration, the machine screws must be locked in place. A conventional way to lock machine screws in place is to employ lock washers under the heads. This has the disadvantage of cutting up the surface of the associated structure when the machine screw is removed for disassembly of the parts. Another common way in which machine screws are releasably locked in place without damage to the part is by using a nylon plug inserted into a hole or groove in the threaded body of the machine screw. When the machine screw is threaded into place, the nylon deforms to accommodate the threads. The compression of the deformed nylon maintains pressure on the threads to provide releasable locking of the machine screw in place.
Nylon is a thermoplastic synthetic polymer composition material so that, when it is heated, it becomes soft. Thus, in applications which include the presence of significant heat, nylon locked machine screws cannot be relied upon. There is need for a self-locking machine screw which can be employed in all environments, including high-temperature environments, as a simple replacement of machine screw without requiring machining of any of the parts with which the machine screw is mated.